This invention relates to apparatus for using the human eye to produce outputs for switching or otherwise controlling machinery and more particularly apparatus for monitoring eye orientation and, upon detecting a predetermined orientation of duration longer than a predetermined time, for producing a signal usable for control of machinery. There are a number of situations where a human being wishes to control certain equipment while at the same time keeping his field of vision within a certain range. Often these situations involve the use of the operator's hands to an extent where additional control requirements for the hands are undesirable. For example, an aircraft pilot under circumstances such as landing desires to keep his eyes trained on the outside world through his windshield. During the landing procedure his hands and feet are also busy with manipulation of the aircraft into the desired landing path. During such times the pilot may also desire to know the indications which appear on one or more of his instruments but it may be risky for him to remove his concentration from the outside scene and glance toward these instruments even for a few seconds. He may also desire to manipulate several switches during the procedure again requiring him to remove his concentration from the outside scene and locate the proper switches for manipulation by his already busy hands.
The present invention is intended to simplify some of the manipulations required by the human operator of an aircraft or other machine and to allow the operator to accomplish some of the manipulations by using eye movements without changing his desired field of view.